In the industry, warehouses are used to store large amounts of goods in an organized manner. Warehouse systems typically employed nowadays encompass a variety of types of storage systems ranging from simple pallet racks, allowing the storage of palletized goods in horizontal rows with multiple levels, to high bay warehouses, allowing the storage of goods in heights of up to 50 meters, for example. Stacker cranes movable in lanes between two opposing rack fronts are typically employed to supply the racks with goods. The space necessary for these lanes is generally lost for the storage of goods, however, and, therefore, these types of systems do not provide an optimal usage of space available in a warehouse.
Compact warehouse systems are another type of storage systems which focus on the efficient use of available space in a warehouse. One example of compact warehouse systems are automated channel storage systems in which multiple storage spaces are provided in the depth of a rack in the form of channels accessible from the front or the back of the rack. Channel vehicles, so called shuttles, are used to move goods within the channels. An exemplary channel storage system is described in WO 2009/132687 A1, for example. In channel storage systems, however, goods within a channel can only be stored and retrieved in a first-in first-out (FIFO) or last-in first-out (LIFO) manner and it is thus not possible to directly access goods at any desired storage space within a channel, such as in the middle of a full channel, for example.
It is thus an object of the present disclosure to provide warehouse system techniques that avoid at least one of these, or other, problems.
According to a first aspect, there is provided a warehouse system comprising a three-dimensional arrangement of storage spaces including a plurality of lanes extending in a longitudinal direction, a plurality of rows extending in a transverse direction, and one or more levels in a vertical direction. One or more cars for carrying goods are arranged in at least one of the plurality of rows, wherein the one or more cars in a respective row are drivable along the respective row in the transverse direction, and wherein the number of the one or more cars in the respective row is less than the number of the plurality of lanes. The warehouse system comprises at least one shuttle drivable to shift goods along at least one of the plurality of lanes in the longitudinal direction.
Due to the three-dimensional structure, the warehouse system may also be called a cubic warehouse system. From the viewpoint of the lanes, each of the plurality of lanes may provide storage spaces one after another in the longitudinal direction of the warehouse system, wherein the number of storage spaces per lane corresponds to the number of the plurality of rows. Similarly, from the viewpoint of the rows, each of the plurality of rows may provide storage spaces one after another in the transverse direction of the warehouse system, wherein the number of storage spaces per row corresponds to the number of the plurality of lanes. In other words, the warehouse system may provide a three-dimensional matrix of storage spaces, wherein, at each intersection of the plurality of lanes and the plurality of rows on a level, a storage space is formed. The longitudinal direction may correspond to a horizontal length of the warehouse system and the transverse direction may correspond to a horizontal width of the warehouse system.
In order to store goods at the storage spaces of the warehouse system, cars for carrying the goods may be employed. Each car may be dimensioned to fit into one storage space and a plurality of cars may be arranged one after another in both lane and row directions (i.e., one car per storage space). The one or more cars in a respective row may be arranged to be drivable (or, more generally, to be movable) along the row in the transverse direction. The number of cars arranged in each row may be less than the number of the plurality of lanes. In this way, it may be ensured that each row at any time comprises at least one free storage space (i.e., a storage space where no car is placed) which can be used to temporarily relocate the cars in the respective row in the transverse direction so that a path in a lane required by a shuttle to access a particular storage space in the longitudinal direction may be cleared. Each car may optionally comprise a removable tray on which the goods may be placed. Goods themselves may be palletized.
While cars may be used to shift goods in the transverse direction of the warehouse system, shuttles may be used to shift goods in the longitudinal direction of the warehouse system. The warehouse system may thus comprise at least one shuttle which is drivable (or, more generally, movable) to shift goods along at least one (preferably each) of the plurality of lanes in the longitudinal direction. The at least one shuttle may pick up goods from a car in a respective lane and shift the goods along the lane as needed. In one variant, the at least one shuttle may comprise a warehouse-wide shuttle which may be relocated between different lanes as well as different levels of the warehouse system. In another variant, the at least one shuttle may comprise level-wide shuttles which may be relocated between different lanes on the same level, but not between different levels. In both variants, relocation of the shuttles in the transverse direction from one lane to another may be carried out through movement of the respective shuttle along a free row of the warehouse system in the transverse direction. The free row may be a dedicated row serving for the purpose of transferring shuttles in the transverse direction which may not be used for the storage of goods. Lifts, on the other hand, may be used to relocate a shuttle from one level to another. In still another variant, the at least one shuttle may comprise separate shuttles for each of the plurality of lanes. In this variant, shuttles do not need to be relocated at all and free rows for relocating the shuttles in the transverse direction may not be required.
When goods are to be retrieved by a shuttle from a particular storage space, it may happen that, in the lane of the particular storage space, other storage spaces may be occupied (by cars and/or goods) that prevent the shuttle from shifting the goods from the particular storage space to an end of the lane, where the goods may be transferred further in other directions as needed. In such a situation, the goods are to be retrieved from a storage space which is not an outermost occupied storage space in a lane. To gain access to the particular storage space for transfer of the goods by the shuttle, a path required to shift the goods by the shuttle from the particular storage space to the end of the lane must be cleared. The warehouse system may thus comprise a control system, such as a warehouse management computer, for example, which, in order to retrieve goods from a particular storage space, may be configured to drive the one or more cars in at least one of the plurality of rows to clear a path in the lane of the particular storage space enabling the at least one shuttle to shift the goods along the lane in the longitudinal direction from the particular storage space to an end of the lane, and drive the at least one shuttle to shift the goods along the cleared path from the particular storage space to the end of the lane.
Clearing the path in the lane of the particular storage space may be carried out in various ways. In one variant, clearing the path in the lane of the particular storage space may comprise driving, for each row from the end of the lane to (but not including) the particular storage space (i.e., including the row at the end of the lane, but excluding the row of the particular storage space), at least one car of the one or more cars in the respective row by at least one storage space in the transverse direction so that the lane of the particular storage space is cleared in the respective row. The cars in each row may be driven in the transverse direction in parallel so that the path in the lane of the particular storage space may be cleared in just a single driving step.
In one variant of the warehouse system, the number of the one or more cars in each of the plurality of rows may be exactly one less than the number of the plurality of lanes. In a particular such variant, among the plurality of lanes, a particular lane may be empty before clearing the path in the lane of the particular storage space, wherein driving the at least one car in the transverse direction shifts a particular car among the one or more cars in the respective row into the particular lane. The particular lane may be a dedicated lane used for temporary storage of cars until retrieving of goods from a particular storage space is complete. The particular lane may be an outermost lane of the warehouse system and the particular car may be an outermost car among the one or more cars in the respective row, for example. When retrieving is complete, the temporarily shifted cars may be shifted back as the cleared path is no longer needed.
In another variant, it is also conceivable that more than one lane among the plurality of lanes is empty for temporary storage of cars. Although this may result in non-optimal use of space in the warehouse system, it may increase throughput when a large number of goods is to be retrieved from the warehouse system simultaneously. Also, it will be understood that, rather than a particular lane which may be empty across all rows, it may be sufficient that each row has at least one empty storage space, while the empty storage spaces of the different rows may be available on different lanes. In this case, provided that cars can be driven independently from each other, shifted cars do not necessarily have to be shifted back to their initial position which may help to save energy.
For driving the cars, various realizations of driving mechanisms are conceivable. For example, each car may have a separate driving device installed at the respective car which may be controlled by the control system, e.g., through signals transmitted to the respective car via wireless transmission. In another variant, only a subset of cars (e.g., only one car) among the one or more cars in a respective row may be drivable, wherein the subset of cars may be releasably coupled to the remaining (non-drivable) cars in the respective row so that the remaining cars can be driven indirectly via the subset of cars. In one particular variant, an outermost car in the respective row may form the subset of cars. In such a case, rather than by a driving device installed at the car, the outermost car may be driven by a driving device (e.g., a linear drive) installed at an end of the respective row, wherein the driving device may be coupled to the outermost car. Before clearing the path in the lane of the particular storage space (i.e., in a normal storage state), the one or more cars in the respective row may be releasably coupled to one another and, when clearing the path, the at least one car which is driven in the transverse direction may be uncoupled from the remaining cars in the respective row while the remaining cars remain at their positions.
It will be understood that, for the driving devices mentioned above, different drive technologies may be used. While electric motors may be one feasible variant, other technologies may be employed, such as magnetic drives including magnetic linear drives, for example. Also, it will be understood that control signals may not necessarily have to be communicated to the cars via wireless transmission. Since, in the normal storage state, the cars in a row may be coupled to one another, wire bound transmission of control signals from one car to another may be conceivable as well. Wire based power supply may be realized in the same manner. The coupling between two adjacent cars may be implemented by a magnetic or a mechanical connection which may be released upon receipt of a corresponding uncoupling signal from the control system.
As described above, in the warehouse system of the present disclosure, cars may be used to shift goods in the transverse direction of the warehouse system and shuttles may be used to shift goods in the longitudinal direction of the warehouse system. To realize such linear movability, the cars may be rail guided and comprise rollers engageable in rails extending along the plurality of rows in the transverse direction. The at least one shuttle may be rail guided as well and comprise rollers engageable in rails extending along the plurality of lanes in the longitudinal direction. To avoid crossings of the rails of the cars and the rails of the shuttles, one of the rails of the cars and the rails of the shuttles may extend at the bottom of the plurality of rows or lanes, and the other one of the rails of the cars and the rails of the shuttles may extend at the top of the plurality of rows or lanes, respectively.
In one particular such variant, the one or more cars arranged in a respective row may be rail guided using rails extending at the bottom of the respective row and the at least one shuttle may be rail guided using rails extending at the top of the plurality of lanes. The at least one shuttle may then be configured to pick up goods from a car by lifting, when the shuttle is positioned above the car, the goods to an extent that allows the goods to be shifted in the longitudinal direction of the respective lane. The goods may be placed on a removable tray on the car, wherein the at least one shuttle may comprise one or more gripping arms extending downwards for lifting the tray from the car. The shuttle and its characteristics will be described in more detail below with reference to a shuttle for retrieving goods in a warehouse system according to the third aspect of the present disclosure.
In the above description, reference to the plurality of lanes and the plurality of rows of the warehouse system was mainly made by referring to a single level of the warehouse system. It will be understood, however, that the storage spaces of the warehouse system may be organized into a plurality of levels in the vertical direction. In this case, the warehouse system may comprise at least one lift drivable to transfer goods from one of the plurality of levels to another one of the plurality of levels. When employing warehouse-wide shuttles, the at least one lift may also be usable to transfer the at least one shuttle from one level to another. In a further variant, the warehouse system may comprise at least two groups of lifts, wherein one of the at least two groups of lifts may exclusively be used for storing new goods in the warehouse system and another one of the at least two groups of lifts may exclusively be used for retrieving stored goods from the warehouse system. In such a variant, it is conceivable that one group of lifts is arranged at one side of the warehouse system (e.g., at a side at which new goods are fed into the warehouse system) and another group is arranged at another side of the warehouse system (e.g., at a side at which retrieved goods are fed out of the warehouse system). A group of lifts may comprise a plurality of lifts, but may also be made up of a single lift only. In this way, an efficient transfer of goods (or shuttles) between the levels of the warehouse system may be achieved.
To further enhance efficiency of transfer between levels, it will be understood that more than two lifts can generally be used in the warehouse system, up to the number of the plurality of lanes or the number of the plurality of rows, for example. It is even conceivable that lifts are provided on all four sides of the warehouse system so that the total quantity of lifts may correspond to twice the number of the plurality of lanes plus twice the number of the plurality of rows. This may especially be helpful in case the warehouse system has a large number of levels, similar to high bay warehouses, where the vertical movement of goods commonly forms a bottleneck.
According to a second aspect, there is provided a method for retrieving goods from a particular storage space in a warehouse system comprising a three-dimensional arrangement of storage spaces including a plurality of lanes extending in a longitudinal direction, a plurality of rows extending in a transverse direction, and one or more levels in a vertical direction. In the warehouse, one or more cars for carrying goods are arranged in at least one of the plurality of rows, wherein the one or more cars in a respective row are movable along the respective row in the transverse direction, and wherein the number of the one or more cars in the respective row is less than the number of the plurality of lanes. The warehouse system comprises at least one shuttle movable to shift goods along at least one of the plurality of lanes in the longitudinal direction. The method comprises moving the one or more cars in at least one of the plurality of rows to clear a path in the lane of the particular storage space enabling the at least one shuttle to shift the goods along the lane in the longitudinal direction from the particular storage space to an end of the lane, and moving the at least one shuttle to shift the goods along the cleared path from the particular storage space to the end of the lane.
The method according to the second aspect may correspond to the method steps performed by the control system of the warehouse system according to the first aspect. Thus, the features described herein with reference to the warehouse system of the first aspect may also be embodied in the steps of the method of the second aspect, where applicable. Unnecessary repetitions are thus omitted in the following.
As in the first aspect, clearing the path in the lane of the particular storage space may comprise moving, for each row from the end of the lane to the particular storage space, at least one car of the one or more cars in the respective row by at least one storage space in the transverse direction so that the lane of the particular storage space is cleared in the respective row. Among the plurality of lanes, a particular lane may be empty before clearing the path in the lane of the particular storage space, wherein moving the at least one car in the transverse direction may shift a particular car among the one or more cars in the respective row into the particular lane.
According a third aspect, there is provided a shuttle for retrieving goods in a warehouse system comprising a three-dimensional arrangement of storage spaces including a plurality of lanes, a plurality of rows, and one or more levels. The shuttle is configured to be movable along at least one of the plurality of lanes at a top of the at least one lane, wherein goods in a storage space are disposed at the bottom of the storage space. The shuttle is configured to pick up the goods by lifting the goods from the bottom of the storage space when the shuttle is positioned above the goods.
The shuttle according to the third aspect may correspond to the at least one shuttle of the warehouse system of the first aspect, and the warehouse system in which the shuttle according to the third aspect is used may correspond to the warehouse system of the first aspect. Thus, those features described above in relation to the at least one shuttle and the warehouse system of the first aspect may be comprised by shuttle and the warehouse system according to the third aspect as well, and vice versa. Unnecessary repetitions are thus omitted in the following.
As in the first aspect, the shuttle may comprise rollers engageable in rails extending at the top of the at least one lane. For driving purposes, the shuttle may comprise a driving device configured to drive the rollers to move the shuttle along the at least one lane. The driving device may be controlled by a control system of the warehouse system, e.g., through signals transmitted to the shuttle via wireless transmission. The driving device may be an electric motor, for example, but may also be based on other drive technologies, such as magnetic drive technologies, for example.
The shuttle may comprise one or more gripping arms extending downwards from a platform of the shuttle for lifting the goods from the bottom of the storage space. In one variant, each of the one or more gripping arms may comprise a rod extending downwards from the platform of the shuttle, wherein the rod comprises a jaw and at a lower end thereof. The rod may be rotatable about its longitudinal axis so as to turn the jaw to grip the goods (e.g., via a pallet or a tray on which the goods are placed). The shuttle may comprise an actuator, such as an electrical actuator, which is configured to rotate the rod to either grip or release the goods. When the shuttle comprises at least two gripping arms, the actuator may be configured to rotate the rods of the at least two gripping arms simultaneously. In such a case, there may be no need for separate actuators for each gripping arm and, rather, all gripping arms may be served by the same actuator.
The shuttle may further comprise a lifting device for lifting the goods when the one or more gripping arms grip the goods. The shuttle may in this case comprise an upper platform and a lower platform, wherein one of the upper and lower platform may be liftable with respect to the other one of the upper and lower platform using the lifting device, and wherein the one or more gripping arms may be fixed to the liftable platform. In one such variant, the rollers of the shuttle may be mounted to the lower platform and the lower platform may thus be fixed in height when the rollers engage the rails extending at the top of the at least one lane. The upper platform may then be liftable with respect to the lower platform using the lifting device, wherein the one or more gripping arms may be fixed to the upper platform so that the gripping arms are lifted together with the upper platform. The lifting device may be an electrically drivable lifting jack, for example.
When picking up the goods from the bottom of the storage space (e.g., from a car positioned at the storage space, as described above), the shuttle may be configured to lift the goods to an extent that allows the goods to be shifted by the shuttle along the at least one lane above the bottom of the at least one lane. This extent may be a minimal distance that is sufficient to shift the goods along the at least one lane without contacting elements at the bottom of the at least one lane. When the goods are placed on a removable tray at the bottom of the storage space (e.g., a removable tray placed on a car, as described above), the shuttle may be configured to lift the tray together with the goods. The goods may optionally be palletized.